In a retrospective study of 59 patients the results obtained with elbow arthrolysis performed for the treatment of posttraumatic stiffness were analyzed. The intraoperative functional result was classified as excellent in all cases, while an average of 27 months after the operation the range of movement was decreased again to varying extents. This deficit correlated with the type of injury, timing of arthrolysis, duration of metal implants and timing and type of postoperative rehabilitation program. The relative increase in function was better after simple fractures, with 47%, than after fracture dislocations, with 35%. After arthrolysis within 3 months of onset of posttraumatic stiffness the range of improvement was 55%, compared with an increase of only 30% after 10 months' stiffness. When arthrolysis was combined with metal removal and the implants had been in place for longer than 9 months the increase achieved was only 15%. Patients mobilized on the 1st day postoperatively lost only 15% of their intraoperative function. If mobilization was delayed to between the 2nd and 5th days, 30% was lost. Changing splints for maximal joint flexion and extension at 4-h intervals resulted in a 35% loss of range of movement postoperatively. In contrast there was a loss of only 17% in the group with combined additional physiotherapy and continuous passive motion. The results show that the prognosis of elbow arthrolysis is determined by optimal operative planning and a meticulous rehabilitation program. The time to arthrolysis should be as short as possible, as should the time to removal of metal implants. The aim of the rehabilitation program is immediate postoperative mobilization.(ABSTRACT TRUNCATED AT 250 WORDS)